Keegan leans an 18-foot ladder against the top of a wall. The bottom of the ladder is 4.5 feet from the base of the wall. What i
s the approximate height of the wall? A 13.5 feet B 16.0 feet C 17.5 feet D 18.5 feet
1 answer:
Answer: C. 17.5 feet
Step-by-step explanation:
The attached photo shows the triangle ABC formed by the ladder and the wall. It is a right angle triangle because one of its angles is 90 degrees. The ladder is the hypotenuse of the triangle. To determine the height of the wall, we would find BC by applying Pythagoras theorem
Hypotenuse^2 = opposite ^2 + adjacent^2
18^2 + 4.5^2 + BC^2
BC^2 = 324 - 20.25 = 303.75
BC = √303.75 = 17.5 feet.
You might be interested in
Answer:
The percentage increase in bird population in the second years is 4% .
Step-by-step explanation:
Given as :
During two years, the population of birds of an island became 7 times more than before.
The the percentage increase in first year = = =40%
Let The percentage increase in second year = = r%
So, According to question
The initial population of bird = x
The increase population of bird =7 times before = 7 x
Now,
The increase population of bird = initial population of bird × (1+ ) × (1+
)
Or, 7 x = x × (1+ ) × (1+
)
Or, = 1.4 × (1+
)
Or, 7 = 1.4 × (1+ )
Or, = (1+
)
Or, 5 = (1+ )
Or, (1+ ) = 5
Or, = 5 - 1
Or, = 4
∴ r = 4 × 100
I.e r = 400
so, The percentage increase = r% = 4
Hence The percentage increase in bird population in the second years is 4% . Answer